Over the course of the last two months of intensive testing we've conducted for our 2011 Buyers' Guide, we've had the opportunity to evaluate four different Bluetooth keyboards that work with the iPad, as well as iOS 4-equipped iPhones and iPod touches. The one we rushed to tell you about was Kensington's KeyFolio, a breakthrough combination of case and keyboard that effectively turns the iPad into a miniature laptop -- let down only by its weak, rubbery keys -- but there are several other noteworthy options that are completely different from one another in design and appeal. They are Apple's Wireless Keyboard ($69), Matias's Folding Keyboard for iPhone, iPad + Mac ($100), and Pyramid Distribution's ProMini Wireless Bluetooth Keyboard ($70, aka Magic-Pro ProMini BT-Touch), and we cover all three in this combined review.

Both as a compromise and as an overall design, the best of the bunch is Apple’s official Wireless Keyboard ($69), which was on the market predating the release of the iPad and has not as yet been changed in any way for iOS devices. Because Apple made only a handful of changes from its Mac keyboard layout to the one used on the official iPad Keyboard Dock, the Wireless Keyboard has the greatest similarity in key functions and feel, yet still omits the several iOS-specific keys such as Home, Picture Frame, Spotlight, and Lock that distinguish Mac keyboards from iOS ones.

The Wireless Keyboard has several advantages over the other keyboards, starting with its design: it is nearly as thin and small as Apple’s latest Mac-specific wired keyboards, with a rear tube for two AA batteries occupying more height than any other part of the metal and plastic design—an element that enables the keyboard to have a modest, ergonomically useful tilt. Batteries tend to run for months without needing replacement, although your experience may differ depending on the brand of batteries you purchase after the included set runs out, and Bluetooth pairing is as easy as with the others: enter a sequence of numbers on the keyboard and hit enter after holding the Keyboard’s power button down to start pairing. The keys are responsive, full-sized, and satisfyingly clicky without becoming grating, and the overall collection of keys is suited to doing just about everything most users could want with an iPad; only a dedicated numeric keypad is omitted, but command keys are included and easy to use. If you’ve ever used a MacBook or iMac keyboard, you know exactly what to expect from this one.

Assuming that the case or bag you’re using has enough space for an 11.1” by 5.2” by 1” item to squeeze inside, and you’re not worried about accidentally snapping the Wireless Keyboard in half, it’s easy enough to carry around; we’ve taken it on cross-country trips without incident. It’s also a great companion to an iPad in a separate stand, superior in versatility on a desk to the iPad Keyboard Dock, but also more expensive given the added cost of the separate stand.

By comparison, Matias’s Folding Keyboard is a different sort of animal altogether. It folds in half to become just about the same width as an iPad is tall, albeit with greater thickness and a much wider wingspan when it’s opened. Matias offers a no-compromises solution that business users in particular may appreciate—a full-sized keyboard, complete with a numeric keypad, 15 F-keys, and all the fixings, including Mac-ready command keys and a softer, quieter feel that’s more akin to traditional PC keyboards. Those familiar with oversized PC desktop keyboards will find that this keyboard requires even fewer compromises than the Apple Wireless Keyboard, but it’s worth noting that its F-keys are non-functional on the iOS devices for features such as music playback and screen brightness; Matias has three separate buttons to control audio volume, and that’s it. Pairing is only slightly more challenging than on Apple’s keyboard, as a dedicated pairing button is recessed next to the power lights on the left, and you need to use a pen tip to trigger it. Two AAA batteries are included to provide power, and a simple black carrying sleeve protects it for travel.

We found typing with the Folding Keyboard to be a little less thrilling than with Apple’s when on a desk, and substantially different—worse, really—on a lap. Matias’s design is wider than even Apple’s full-sized, numeric keypad-equipped desktop keyboard, and doesn’t become firm in the center when unfolded, so unless you’ve placed it on a flat surface, it gives in the middle when you’re typing. As we’re used to Apple’s keyboards, and big fans of the last two generations of the company’s designs, we found the Folding Keyboard’s keys to be a little squishy for our liking. Though they were dramatically better than the ones on Kensington’s KeyFolio, we still found ourselves making numerous errors that we wouldn’t have made on the Apple keyboards, quite possibly twice as many in each sentence. Acclimation helps over time, but we still like the feel and responsiveness of Apple’s keys the best.

The last of the Bluetooth keyboards is Pyramid Distribution’s ProMini, and it’s also the one that requires the most accommodation and subsequent correction. What we really liked at first about ProMini was its size—it measures only 5.8” long by 2.3” deep and .5” thick, seemingly ideal for carrying around with an iPhone or iPad for greater typing power, and it has both the most on-paper functionality and the easiest power-on interface. Flip a switch on its side for power on/off, and hit a Bluetooth key when you need to pair the device, both really simple; it also includes a rechargeable battery and USB charging cable, which are both found in Kensington’s KeyFolio but aren’t components in either of the other keyboards. Unlike all of the other options, there’s also a touchpad on the right side of the keyboard that can be used with computers (but not iOS devices) for cursor control, plus a laser pointer just because Chinese companies seem to build them into things for the sake of doing so. It’s worth a brief mention at this point that ProMini wasn’t developed by Pyramid, and certainly isn’t iPad-specific; it’s also sold as the Rii Mini Wireless Keyboard for computers and home theater PCs.

While we wanted to love and use ProMini a lot, we actually found it challenging to type on. This entire review was written on the keyboards as we were describing them, except that we abandoned ProMini part way through the last paragraph because typing accurately was so difficult and slow—a problem we’d attribute more to its attempts to be useful for non-iOS devices than flaws in its keys. Actually pressing the keys led to satisfying little semi-clicks, and their surface area is greater than on the iPhone or iPod touch, so our larger-than-infant-sized fingers had no problem actually typing out individual letters; frequent texters may eventually be able to accommodate them. Unfortunately, the presence of the touchpad surface next to the keyboard makes holding and dual-hand typing on ProMini more difficult than it should be, and an unorthodox key arrangement leads to awkward shifting for capitalization, as well as the absence of a command key for cutting, pasting, and the like. While track and volume controls are included, you need to hold a Fn key before you can use any of them.

Ultimately, Apple’s Wireless Keyboard strikes us as the best overall iOS-ready compromise between the options available today. While its $69 asking price feels just as steep for the iPad and other iOS devices as it does on Apple’s computers, the keyboard’s physical size, quality, and ease of use strike a balance that none of its rivals have been able to match. It’s only an inch wider unfolded than Matias’s much more expensive keyboard is when folded, and it’s thinner, less expensive, and more key-compatible with the iPad, as well. The ProMini keyboard is obviously substantially smaller, but it adds the least to the iOS devices in terms of user experience; unless you also want to use it with a computer or as a prop for a laser light show, you’d do just as well to save your $70 and use the keyboards built into Apple’s devices. We’d really like to see third-party developers become more aggressive at developing affordable Bluetooth solutions that have specific keys and form factors for portable iOS use, but until something better comes along, Apple’s Wireless Keyboard is the top alternative.

Editors' Note: iLounge only reviews products in "final" form, but many companies now change their offerings - sometimes several times - after our reviews have been published.
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